How to to split an element to make a rotation point to animate a follow path
Take two:



I looked into the Follow Path constraint a bit more, but could not come up with anything. I instead decided to rig the bus. Basically, I added a base bone with a Follow Path constraint and two bones on either end with Follow Path constraints and an Offset: value to make sure they stayed at the front and rear of the bus. I then added two bones for the two halves of the bus. They are following the base bone's movements (parented) and have a Track To constraint so they point towards the two end bones. I did all the weight painting myself, so it would take forever to write a lengthy tutorial. Instead, I explained what I did, and am including a second .blend file. Note that you may want to adjust the start and end values in the .blend file.